Pump-piston.



E. C. VEZI.

PUMP PISTON.

APPucATloN FILED JULY 6.1914.

Patented Nov. 30, 19l5.

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WITNESSES Pv-[6,11

ELMER C. VEZIE, DI WASHINGTON, `PII?1\T1\TSYLV.A1`1'I.A..

PUMP-PISTON.

Specification of Letters Patent.

Application iled'July 6, 1914. Serial No. 849,042.

i and State of Pennsylvania, have invented a new and useful Pump-Piston,ofwhich the following .is a full, clear, and eXactdes'cription,reference being had to the accompanying drawings, in which- Figure l isa longitudinal section of a portion of a pump barrel and piston, andshowing my invention. Fig. 2- is a similar view with the packing sleeveof the piston expanded. Fig. 3 is a side elevation of the end portion ofthe piston, and Figs. 4 and 5 are sections taken respectively on thelines IV-IV and V-V of Fig. 1.

Myinvention has relation to pump pistons, and is designed to provide animproved arrangement ofthe piston packing, whereby a tight joint is atall times insured between the piston and pump barrel or cylinder withoutthe use of cup leathers or Washers, such as are commonly used.

In accordance with my invention, I provide the piston with an extendedpacking sleeve of any suitable flexible material; and also provide meanswhereby the pressure of the fluid being pumped is made available toholdthis packing sleeve in its distended packing position.

My invention is applicable to various forms and classes of pumps, theparticular form. shown in the drawing being merely illustrative of oneembodiment'of my invention.

In the drawings, the numeral 2 designates a portion of a pump'barrel orcylinder and 3 the piston rod.

4 is a packing sleeve of any suitable flexible material which is seatedaround the lower end portion of the piston rod between i suitableconfining members at its ends, such as the sleeves or ferrules 5. One ofthese sleeves or ferrules is made removable and may be screwed uponathreaded portion 3 of said rod. Secured Von the end of the rod,preferably by screwing it on the threaded portion 3a of the rodagainst-the end of the adjacent ferrule 5, is an end pieceor head 6having preferably a plurality of inlet openings 7 These inlet openingsvextend into an internal chamber 8 of the head, said chamber having avalve sea't at 9 controlled by an inwardly opening check valve 10H ofany suitable character. The portion 3a of the piston rod has alongitudinal internal port 11 communicating with the chamber 8 and alsohaving one or more radialopenings v12 which extend out through itsperipheral wall so as' to conduct the fluid directly against the innersurface of the packing sleeve 4. Y Y

It will be readily seen that on each alternate stroke of the piston, thevalve 10 will be opened by the opposing pressure of the fluid beingpumped, thereby admitting such fluid to the interior of the chamber 8and 1nto the port l1 until such chamber and port are completely filled.On the reverse strokes the check valveis seated, thus confining thefluid. In this manner the pressureof the Patented Nov. ao, isis.

fluid is made available at all times to hold the packing sleeve in adistended position such as illustrated in Fig. 2, The packing can thusbe used until itis worn very thin without its efliciency beingmaterially impaired.

It will be obvious that the particular construction and arrangement 'ofthe various parts may be varied considerably in the ap` plication of theinvention to various forms of pumps and pistons, within the scope of theappended claims.

I claim:

1. A pump piston having'an expansible packing sleeve on the outersurface thereof,

means for tightly securing both ends'of they sleeve to the piston, therebeing a chamber within said piston having fluid under pres-- suretherein, ports connecting the pressure chamber with a space between thesleeve and the piston whereby the packing sleeve is normally expanded,there being a port communicating with said Achamber and a check valve insaid port for admitting and retain- -ing fluid under pressure 'in saidchamber;

substantially as described.

2. A pump piston having an eXpansible packing sleeve on the outersurface thereof, means for 'securing both ends on the sleeve to thepiston, there being a pressure chamber within the piston, portsconnecting the pressure chamber with a space between the sleeve and thepiston, and means for admitting and retaining fluid under pressurewithin said chamber whereby the packing.

sleeve is normally expanded; substantially as described.

3. A pump piston having an expansible packing sleeve on the outersurface thereof, ferrules for connecting the ends of the sleeve to thepiston, there being a pressure chamber Within said piston closed at oneend, ports connecting the pressure chamber with a space between thesleeve and the piston, there being an opening at the other. end of saidchamber for admitting fluid under pressure to said Chamber,` and a checkvalve for controlling the admission of said Huid and re`v taining itWithin said chamber; substantially as described..

4. The combination of a force pump having a barrel or cylinder and apiston rod within said barrel, said piston rod having an expansiblepacking sleeve surrounding it, means for connecting both ends of saidsleeve to the piston rod to form air tight joints between the ends ofthe packing sleeve and the piston rod, there being a pressure chamberWithin said piston rod, said pressure chamber being closed at one endand open at the end toward the pump chamber,

ports connecting the pressure chamber with the space between the sleeveand the piston, and a check valve for controlling the opening leading tosaid pressure chamber, said check valve being arranged to be opened onthe inward stroke of the piston to force fluid into the pressure chamberand the space between the piston rod and the packing sleeve, said checkvalve being also arranged to retain said Huid under pressure within thepressure chamber to normally hold the packing sleeve against the pumpcylinder to maintain a tight joint between the packing sleeve and thepump cylinder; substantially as described.

'In testimony whereof, I have hereunto set' my hand.

ELMER C. VEZIE. -Witnesses G. W. LINDSAY, JAS. C. BRYANT.

